The objective of this project is to examine new vaccine delivery systems for the administration of mucosal and parenteral administration of pertussis antigens. The B. pertussis protein Tcf has been expressed in Vibrio cholerae using the E.coli nirB promoter. Mice were immunized four times intranasally with recombinant Vibrios prior to challenge with an aerosol of B. pertussis. Intranasal administration of V. cholerae expressing Tcf induced a significant reduction in bacterial colonization of the tracheas compared to animals immunized with V. cholerae alone. Such an outcome is consistent with the proposed role for this protein in tracheal colonization. A project to evaluate DNA vaccines as a means of generating a protective response to B. pertussis antigens has been initiated. Fragments of the Tcf and pertactin genes have been cloned in a DNA vaccine vector and will be delivered to mice. These proteins have been chosen since both have been shown to be effective immunogens in the mouse aerosol challenge model for pertussis.